Download - java_lect_001
• Structure of Java programs
• Input and output to screen with Java program
• Statements
• Conditional statements
• Loop constructs
• Arrays, character and string handling
• Functions (if time permits)
Syllabus
1. Java 2: The Complete Reference
– Patrick Naughton, Herbert Schildt
2. Thinking in Java (http://www.mindview.net/Books/TIJ/)
– Bruce Eckel
3. Richard G Baldwin’s “Introductory Java Programming
Tutorial” on: http://www.dickbaldwin.com/tocint.htm
Books & References
• Structure of Java programs
• Compiling and running the program
• Printing messages to the screen
Contents for Today’s Lecture
Some Basics
Q. What is a program?Ans. A sequence of instructions that a computer can interpret and execute.
Q. Why Java and not Hindi / Marathi / English?Ans. Since, so far, computer is not intelligent enough to understand natural languages.
class class-name {
public static void main(String args[]) {
statement1;
statement2;
…
…
}
}
Structure of Java Programs
“First.java”
class First {
public static void main(String args[]) {
System.out.println(“Hello World”);
}
}
Example Program
Compiling: is the process of translating source code written in a particular programming language into computer-readable machine code that can be executed.
$ javac First.java
This command will produce a file ‘First.class’, which is used for running the program with the command ‘java’.
Running: is the process of executing program on a computer.
$ java First
Compiling & Running the Program
1. System.out.println(“Hello World”); – outputs the string “Hello World” followed by a new line on the screen.
2. System.out.print(“Hello World”); - outputs the string “Hello World” on the screen. This string is not followed by a new line.
3. Some Escape Sequence –
• \n – stands for new line character
• \t – stands for tab character
About Printing on the Screen
• Some common errors in the initial phase of learning programming:
- Mismatch of parentheses
- Missing ‘;’ at the end of statement
- Case sensitivity
• The best way to learn programming is writing a lot of programs on your own.
Some Tips About Programming
1. Write a program which prints the following information about at least 5 persons:
NAME MAIL-ID EMPLOYEE-CODE PHONE
Eg. Umesh umesh@cse p03161 25764728
Salil salil@cse p03160 25764728
Each entry should be on a separate line.
2. Write a program that prints the following line on the screen along with quotes.
“Can we print ‘\’ with System.out.println() statement?”
Some Assignments